Monitoring ON-Resistance of MOSFET Devices in Real Time for SVPWM-VSI With Direct Compensation

One of the major causes for the operation failure and/or malfunction in a voltage source inverter is from power semiconductor devices, such as MOSFET and IGBT. Especially, under harsh operating environments, the power devices face various mechanical/thermal challenges, which can increase the equipment/device failure rate and cause unexpected interruptions and/or serious safety issues. This paper focuses on estimating the ON-resistance of the MOSFET/IGBT devices in real time while operating in space-vector pulsewidth modulation mode to monitor the status on power MOSFET/IGBT devices in real time, hoping that it can avoid those unexpected interruptions for safety. Since the increase in ON-resistance of the power MOSFET is identified as the fault signature, it is worthwhile to measure ON-resistance to prevent the output voltage distortions and the amplitude reduction from the set reference voltage in advance.